PC Sound-Card Signal-Generator-Interface : 6 Steps - Instructables
VT DSO-2810E: PC based USB 8~16Bit 100MSPS 40MHz Oscilloscope, Spectrum Analyzer, 10-bit 200MSPS 60MHz AWG Signal Generator | Virtins Technology
Sound-Card Signal Generator Interface Adds Variable Offset Control | Electronic Design
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VT DSO-2820: PC based USB 8~16Bit 200MSPS 80MHz Oscilloscope, Spectrum Analyzer, 10-bit 6.25MSPS 150kHz AWG Signal Generator | Virtins Technology
900w China Digital High Frequency Ultrasonic Signal Generator 28khz/40khz Used In Cleaning Machine - Ultrasonic Cleaner Parts - AliExpress